Lessons from large interventional trials on antihypertensive therapy in chronic renal disease

Studies in animal models have shown a convincing role for hypertension in the progression of renal disease. However, in clinical studies, the relationship between hypertension and progression is difficult to demonstrate owing to confounding factors such as age, gender, race, difficulty in identifying blood pressure (BP) parameters that correlate with progression, abnormal circadian BP pattern, and many non-haemodynamic factors of progression. A recent meta-analysis of several studies has shown that pharmacological agents that reduce both BP and proteinuria (U(P)), particularly angiotensin-converting-enzyme (ACE) inhibitors, significantly slow the rate of progression of chronic kidney disease. In these studies, lower achieved BP in patients both with and without U(P) was associated with slower decline in renal function. ACE inhibitors are effective BP-lowering agents and are associated with improved preservation of renal function compared with antihypertensive regimens without ACE inhibitors. The protective effect of ACE inhibition is additional to the effect of reducing BP and U(P).